Our findings suggest LA mechanical functional decays in association with increasing age and higher blood pressure, which seem to be compensated for by augmentation of atrial pump function. We have also provided age- and sex-stratified reference values for strain and SR based on a large-scale Asian population.

ObjectivesEpicardial fat was closely related to atrial fibrillation (AF). Transthoracic echocardiography (TTE) has been proposed to be a convenient imaging tool in assessing epicardial adipose tissue (EAT). The goal of the present study was to investigate whether the EAT thickness measured on TTE was a useful parameter in predicting procedural outcomes of AF ablations.Methods and ResultsA total of 227 paroxysmal AF (PAF) and 56 non-paroxysmal AF (non-PAF) patients receiving catheter ablations from 2008-2010 were enrolled. Echocardiography-derived regional EAT thickness from parasternal long-axis view was quantified for each patient. Free of recurrence was defined as the absence of atrial arrhythmias without using antiarrhythmic agents after ablations. The mean EAT thickness of the study population was 6.1 ± 0.8 mm. Non-PAF patients had a thicker EAT than that of PAF patients (7.0 ± 0.7 mm versus 5.9 ± 0.7 mm, p value <0.001). During the follow-up of 16 ± 9 months, there were 95 patients (33.6%) suffering from recurrences of atrial arrhythmias. Non-PAF, chads2 score, left atrial diameter and EAT thickness were independent predictors of recurrence after catheter ablations. At a cutoff value of 6 mm for PAF and 6.9 mm for non-PAF, the measurement of EAT thickness could help us to identify patients at risk of recurrences.ConclusionsEAT thickness may serve as a useful parameter in predicting recurrences after AF ablations. Compared to other imaging modalities, TTE can be an alternative choice with less cost and time in assessing the effects of EAT on ablation outcomes.

Background & Aims Metabolic syndrome (MetS), characterized by abdominal obesity, atherogenic dyslipidemia, elevated blood pressure, and insulin resistance is a major public health concern in the United States. Omega-3 fatty acids have been relatively well studied in relation to many individual cardiovascular risk factors; however, their effects on MetS are not well established. Methods We conducted a cross-sectional study consisting of 4,941 participants from the National Heart, Lung, and Blood Institute (NHLBI) Family Heart Study to assess the relation of dietary omega-3 fatty acids with the prevalence of MetS. Omega-3 intake was assessed using a food frequency questionnaire and we used generalized estimating equations to estimate adjusted odds ratios for prevalent MetS. Results Our study population had a mean age (SD) of 52.1 (13.9) years and 45.9% were men. The mean (SD) of dietary omega-3 fatty acids was 0.25g/day (0.27). From the lowest to the highest quintile of dietary omega-3 fatty acids, multivariable adjusted ORs (95% CI) for MetS were 1.00 (ref), 0.90 (0.72–1.13), 1.03 (0.82–1.28), 0.94 (0.74–1.18), and 0.99 (0.77–1.25), respectively. In a secondary analysis, neither fish consumption nor dietary alpha-linolenic acid was associated with MetS. Conclusions Our findings do not support an association between dietary omega-3 fatty acids and MetS in a large US population.

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Abstract-Endothelial cells form gap junctions that, according to vessel type, may be composed of up to 3 types of connexin, connexin37, connexin40, and connexin43. Although changes in connexin expression have been linked to growth and injury in cultured endothelial cells, information on connexin expression in regenerating endothelium in situ is lacking. We investigated gap junction distribution and expression of all 3 endothelial connexins during healing in rat carotid artery after denudation injury. En face viewing of the vascular luminal surface by means of immunoconfocal microscopy was used to examine the spatial and temporal expression pattern of the endothelial connexins. Gap junction spots labeled by specific antisera against connexin37, connexin40, and connexin43 were quantified 7, 14, and 28 days after injury, and the relations among the connexins were examined by using colocalization analysis. Complementary electron microscopy was also conducted. After injury, the regenerating endothelium initially expressed small, sparse gap junctions, the numbers of which progressively increased to values equivalent to those of controls. Although connexin40 gap-junctional spot size and area returned to uninjured levels by 28 days after injury, connexin37 and connexin43 spot size and area exceeded those of the uninjured artery (PϽ0.05). Double-label analysis showed that even though colocalization of connexins to the same gap-junctional spot is a common feature, the extent of colocalization was time dependent (Ͼ80% in the intact artery at postinjury day 28 and Ͻ70% at postinjury days 7 and 14, PϽ0.01). We conclude that distinct alterations in expression of the 3 connexins are associated with regeneration of the arterial endothelium in situ, implying different intercellular communication requirements during the various phases of the healing process.

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We have previously shown that left atrial-pulmonary vein tissue (LA-PV) can generate reentrant arrhythmias (atrial fibrillation, AF) in wild-type (mXinα+/+) but not in mXinα-null (mXinα-/-) mice. With the present experiments, we investigated the arrhythmogenic activity and the underlying mechanisms in mXinα+/+ versus mXinα-/-LA-PV.Electrical activity and conduction velocity (CV) were recorded in LA-PV by means of a MED64 system. CV was significantly faster in mXinα+/+ than in mXinα-/-LA-PV and it was increased by 1 μM isoproterenol (ISO). AF could be induced by fast pacing in the mXinα+/+ but not in mXinα-/-LA-PV where automatic rhythms could be present. ISO increased the incidence of AF in Xinα+/+ whereas it increased that of automatic rhythms in mXinα-/-LA-PV. In LA-PV with the right-atrium attached (RA-LA-PV), automatic rhythms occurred in all preparations. In mXinα+/+ RA-LV-PV simultaneously treated with ISO, strophanthidin and atropine, the incidence of the automatic rhythm was about the same, but AF increased significantly. In contrast, in mXinα-/-RA-LA-PV under the same condition, the automatic rhythm was markedly enhanced, but still no AF occurred. Conventional microelectrode techniques showed a longer APD 90 and a less negative maximum diastolic potential (MDP) in mXinα-/-than mXinα+/+ LA-PV tissues. Whole-cell current clamp experiments also showed a less negative MDP in mXinα-/-versus mXinα+/+ LA-PV cardiomyocytes.The fact that AF could be induced by fast pacing under several conditions in mXinα+/+ but not in mXinα-/-LA-PV preparations appears to be due to a slower CV, a prolonged APD 90 , a less negative MDP and possibly larger areas of conduction block in mXinα-/-myocardial cells. In contrast, the non-impairment of automatic and triggered rhythms in mXinα-/-preparations may be due to the fact that the mechanisms underlying these rhythms do not involve cell to cell conduction.